[Bridge] [PATCH net] bridge: netlink: fix slave_changelink/br_setport race conditions

[David Miller]

From: Nikolay Aleksandrov <razor at blackwall.org>
Date: Wed, 22 Jul 2015 13:03:40 +0200

> From: Nikolay Aleksandrov <nikolay at cumulusnetworks.com>
> 
> Since slave_changelink support was added there have been a few race
> conditions when using br_setport() since some of the port functions it
> uses require the bridge lock. It is very easy to trigger a lockup due to
> some internal spin_lock() usage without bh disabled, also it's possible to
> get the bridge into an inconsistent state.
> 
> Signed-off-by: Nikolay Aleksandrov <nikolay at cumulusnetworks.com>
> Fixes: 3ac636b8591c ("bridge: implement rtnl_link_ops->slave_changelink")

Applied and queued up for -stable, thanks.